- CFA Exams
- CFA Level I Exam
- Study Session 3. Quantitative Methods (2)
- Reading 11. Hypothesis Testing
- Subject 8. Hypothesis Tests Concerning the Mean: T-Test vs. Z-Test

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**CFA Practice Question**

As sample size increases, ______

A. critical values for t decrease.

B. degrees of freedom decrease.

C. confidence interval width increases.

**Explanation:**As sample size increases, degrees of freedom increase and critical values for t decrease. Thus, the amount added to or subtracted from the sample mean to create the confidence interval will decrease. Therefore, confidence interval width will decrease.

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**User Contributed Comments**
4

User |
Comment |
---|---|

aakash1108 |
degrees of freedom increase, critical values decrease! |

rrichmondo |
makes sense |

showmethemoney |
nice question |

yassine |
An increase in sample size would decrease the standard error. As a result CV decreases |